Add route london Fenchurch Street to Shoeburyness on the mainline via basildon. London Fenchurch Street to Grays via Purfleet. If you do this route(Fenchurch Street to Grays via Purfleet) then add the HS1 trains and tracks as a layer alongside C2C between Dagenham dock and rainham. Another suggestion is london Fenchurch Street to Southend Central via tilbury
Anything special about the route? Stopping patterns? Notable landmarks? Why this route in particular? Which trains and why?